User's Manual

User's ManualD-6
INTERFACE INFORMATION
Data Transmission Timing
In unidirectional mode (conventional Centronics interface), this printer
guarantees the received data when the Data and Data Strobe signals from the
computer have the following timing with respect to the Busy and
Acknowledge
signals from the printer.
T5 T6
T1, T2, T3 > 1 µs
T4 < 1 µs
0 µs < T5 < 3 µs
2 µs < T6 < 6 µs
T1
Data 1 to Data 8
Data Strobe
BUSY
Acknowledge
T2 T3
T4
In bidirectional mode (nibblemode), this printer can send data to the compu-
ter. Data is sent in units of four bits (nibble) using four output signal lines as
data paths. The following outlines one byte of data sent during reverse data
transfer phase in nibble mode.
Data Available (*)
X Flag
Ack Data Req
Printer Busy
Host Busy
(from CPU)
Printer Clock
Data bit 4
Data bit 5
Data bit 6
Data bit 7
Data bit 0
Data bit 1
Data bit 2
Data bit 3
1284 Active
(from CPU)
* Data Available is assigned for the cable.